COPENHAGEN, Denmark (AP) — Norwegian oil company Statoil said Thursday it may have relied too heavily on Algerian military protection at its Ain Amenas gas facility, which was attacked by armed terrorist in January.

“There is reason to question the extent of their reliance on Algerian military protection,” Statoil said In a report on the incident.

An al-Qaida-linked militant group stormed the facility, jointly run by BP, Statoil and the Algerian state company Sonatrach, on Jan 16. In the ensuing standoff with Algerian forces 40 workers were killed, along with 29 militants.

“Our assessment was that the Algerian forces had the capacity to withstand an attack,” Statoil CEO Helge Lund said. “We as a company should have been closer to the security work locally in Algeria. That we have improved now.”

Torgeir Hagen, who headed Statoil’s investigation, said the assault was unprecedented.

Inner security at the site — including protective barriers, unarmed guards and access control — was the responsibility of the joint venture while the outer security was in the hands of the Algerian military units, according to the report.

Algerian troops couldn’t “prevent the attackers” and security measures failed “to withstand or delay an attack of this scale, and relied on military protection working effectively,” he told reporters at the company headquarters in Norway.

“We must remember that the responsibility for the killing of 40 innocent people alone lies with the terrorists,” Statoil board chairman Svein Rennemo added.

Algeria has bristled at any criticism about how they handled the crisis. The storming of the site by commandos was portrayed as a great victory, and the nation’s president praised the military for its performance in taking back the gas plant.

An investigation into the attack by the government in March faulted private security firms charged with the installation’s protection and announced that henceforth the military would be responsible for protecting the energy sites in Algeria.

Security has since been boosted at all sites around the country.

Since the attack, Statoil has not had any of its employees at Algerian sites. The 88-page report didn’t address the company’s future in the north-African country.

In Britain, the incident is subject to a coroner’s inquest assisted by a police investigation.

“BP co-operated with Statoil’s investigation and will support all official investigations carried out by relevant authorities and review all outcomes to determine what can be learned for the future,” the British company said.

“Because of the nature of the incident and the fact that the response was an Algerian military operation, there are many questions arising which BP is not in a position to answer, including how the terrorists were able to breach the military zone to attack the plant,” BP added.